The base f430 is like 2976 lbs and 550hp. In order to achieve the same lb/hp ratio, an m3 has to have more 650 hp! When you take into account the f-cars chassis and aerodynamics advantage over the m3, the gap gets wider.

-SZ

The F430 has 490 HP but weighs 2,976 lbs.

It's faster than any M3. I've rented a F430 three times and it's faster than my E92/E90 M3.